Compilare: main.cpp: In function 'int main()': main.cpp:75:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("harbingers.in", "r", stdin); ^ main.cpp:76:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("harbingers.out", "w", stdout); ^ main.cpp:79:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ main.cpp:82:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &u, &v, &d); ^ main.cpp:88:49: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &mes[i].first, &mes[i].second); ^ main.cpp: In function 'void dfs(int, int)': main.cpp:69:9: warning: 'top1' may be used uninitialized in this function [-Wmaybe-uninitialized] top = top1; ~~~~^~~~~~ main.cpp:70:14: warning: 'ind' may be used uninitialized in this function [-Wmaybe-uninitialized] stk[pos] = ind; ~~~~~~~~~^~~~~ main.cpp:70:14: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized]